JP4267124B2 - Resin cap - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a resin cap excellent in openability, and particularly to a resin cap suitably applied to milk bottles.
[0002]
[Prior art]
Conventionally, milk bottles have been provided with a paper cap fitted into the bottle mouth and a cover made of a resin film applied thereto. In such a cap, a special opener is required for easy opening, and a cap that can be easily opened without the opener has been desired.
In order to solve such a problem, an inner plug that protrudes downward from the center portion of the top plate portion and fits inside the container mouth portion is formed, and a ridge that engages the container mouth portion is formed on the inner surface of the skirt portion. In addition, there has been proposed a resin cap characterized in that a breakable thin portion is provided on both sides of the opening tab (Japanese Utility Model Publication No. 47-13109). This cap is capable of breaking the thin-walled portion by pulling up the tab for opening and removing the cap from the container mouth by breaking the cap, and does not require a special opening tool. Is preferable.
[0003]
[Problems to be solved by the invention]
However, in such a cap, a certain amount of force is required when the skirt portion is broken along the thin-walled portion, and thus the contents may be spilled when the cap is opened. Especially when the contents are applied to contents for a wide range of consumers from children to the elderly, such as milk, it is necessary to be able to open the bottle easily and reliably without applying force. is there.
The resin cap configured as described above is fitted by sealing the container by filling the contents with the protrusions on the inner surface of the skirt part of the cap and the concave part of the container mouth part by engagement with the stopper. To do. At this time, in general, in order to improve the sealing performance of the cap and improve the storage stability of the contents, the protruding amount inward of the ridge provided on the inner surface of the skirt portion of the cap is increased and the container mouth portion is strongly fitted. However, if the fitting becomes stronger, the opening force also increases, and the opening property becomes a problem. Moreover, in order to prevent the thin-walled portion from being broken at the time of plugging, if the thin-walled portion is excessively strengthened, there is also a problem that the opening of the thin-walled portion becomes extremely difficult, which makes it difficult to manage the dimensions of the thin-walled portion. .
[0004]
Accordingly, the object of the present invention is to provide an excellent sealing performance and to be able to open the plug easily and reliably, and also to have a good stoppering property and moldability, and to balance the contradictory performance of the sealing property and the opening property. It is to provide an easy resin cap.
[0005]
[Means for Solving the Problems]
According to the present invention, the top plate portion provided with the sealing engagement portion with the container mouth portion on the inner surface side, and the radially inwardly engaging projection portion that is engaged with the outer peripheral surface of the container mouth portion are provided on the inner surface side. In addition, in the resin cap comprising a skirt portion having a plug opening tab projecting radially outward at a part below the outer surface side, the locking projection portion is an upper portion whose diameter is reduced downward and reaches the top portion And a stopper part whose diameter increases downward from the top part and a lower end consisting of a top part or a notch part located below the top part , and a plurality of parts distributed in the circumferential direction. Each of the plurality of locking projections has a stoppering guide portion at least in the circumferential direction or in the vicinity thereof, and has a notch portion between the stoppering guide portions. A resin cap is provided.
[0006]
In resin cap of the present invention, the locking projection, on the outer surface side of the scan cart portion provided lower end window-like recess with the exception of the skirt portion is dispersed in the circumferential direction, the window-like recess It is particularly preferable that is provided in a positional relationship overlapping with the stopper guide portion in the radial direction.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
[Action]
In order to improve the sealing performance of the cap, the cap diameter at the top of the locking projection is small, that is, the locking projection protrudes inward and firmly engages with the outer peripheral surface of the container mouth. It is desirable that On the other hand, if the locking projection protrudes greatly inward, the cap skirt becomes thick and lacks flexibility, resulting in poor openability.
From this point of view, the resin cap of the present invention has an upper portion and a lower portion of the locking projection composed of an upper portion reaching a top portion with a diameter decreasing downward and a lower portion extending a diameter downward from the top portion and reaching a lower skirt portion. The lower stopper guide part retains the locking force with the container mouth and is provided with a notch below the top of the locking protrusion, so that the function of the locking protrusion is reduced. In other words, the cap is made flexible to improve the openability.
[0008]
In addition, the stopper protrusion is provided with a stopper guide part whose diameter increases downward from the top part and a notch part that partially thins the skirt part. Is expanded in the radial direction, the cap is smoothly introduced into the container mouth along the stoppering guide, and the upper part of the locking projection and the outer peripheral surface of the container mouth (the protrusion is formed on the outer periphery of the container mouth). In this case, the lower surface of the projecting portion is engaged, and damage to the cap in the stopper is effectively prevented.
[0009]
Embodiment
A preferred embodiment of the resin cap of the present invention will be described with reference to the accompanying drawings. In addition, although embodiment described below is demonstrated as what is applied to the milk bottle currently distribute | circulated generally, this invention is not limited to this naturally.
1A and 1B are diagrams for explaining the outline of a resin cap of the present invention, FIG. 1A is a bottom view, FIG. 1B is a side sectional view of a section XX in FIG. C) is a side view of (A).
[0010]
The resin cap of the present invention, indicated as a whole by 1, comprises a top plate portion 2 and a skirt portion 3 depending from the edge of the top plate portion 2, and a plurality of locking projections 4 are provided on the inner surface of the skirt portion 3. ing. As will be described in detail later, the locking projection 4 is composed of an upper portion 6 and a lower portion 9 composed of a stopper guide portion 7 and a notch portion 8. In addition, an inner plug 10 that is fitted inside a container mouth (not shown) is provided in an annular shape on the inner surface of the top plate portion 2. Further, the skirt portion 3 is provided with an opening tab 11 for opening. Furthermore, a plurality of window-like recesses 12 are provided on the outer surface side of the skirt portion 3 so as to be distributed in the circumferential direction except for the vicinity of the lower end of the skirt portion 3.
[0011]
2 and 3 are enlarged side sectional views for explaining in detail the locking protrusion 4 of the cap shown in FIG. The locking projection 4 includes an upper portion 6 of a region indicated by m and a lower portion 9 of a region indicated by n with the top portion 5 as a boundary. The upper part 6 is reduced in diameter downward to reach the top part 5, and the lower part 9 is arranged in a circumferential direction on the stoppering guide part 7 and the stoppering guide part 7 whose diameter increases downward from the top part 5. It consists of a notch 8 which is adjacent and whose upper edge is located at the top 5.
The upper edge of the notch 8 shown in FIGS. 2 and 3 is located at the top 5, but the purpose of the notch can be achieved if the thickness below the thickest top 5 is reduced. The upper edge of the part does not necessarily have to be the top.
[0012]
Further, as is apparent from FIG. 1A, it is preferable that a plurality of the locking projections 4 are provided in the circumferential direction except for the portion of the opening tab 11.
That is, without providing the locking projection 4 at the portion corresponding to the opening tab 11, the skirt portion of this portion is made thin, thereby providing flexibility to the skirt portion of the opening tab 11 portion. As a result, the cap can be easily deformed by pushing up the opening tab 11 and the opening performance can be improved. Further, by providing a plurality of locking projections 4 in the circumferential direction without being continuous, a thin portion 13 is formed between the locking projections, and the entire skirt portion is imparted with flexibility to be opened. It is possible to improve the plugability and plugging performance.
[0013]
Further, each of the locking projections 4 preferably has a stoppering guide portion at least in the circumferential direction or in the vicinity thereof, and has a notch portion between the stoppering guide portions.
That is, as is clear from FIGS. 1A and 1B, the locking projections 4a provided on both sides of the unsealing tab 11 have notches 8 between the stoppering guide portions 7a and 7b. Have. Further, the locking projections 4b on the portions other than both sides of the opening tab 11 are provided with stoppering guide portions 7a and 7b at both ends, and further provided with a stoppering guide portion 7c and three stoppering guide portions at the center. Thus, two notches 8a and 8b are formed.
As described above, since the notch is sandwiched between the stoppering guides, the cap is smoothly introduced into the container mouth along the stoppering guides on both sides during stoppering. The upper end of the part does not become a resistance.
[0014]
In the specific example shown in FIG. 1, the locking protrusions on both sides of the opening tab are provided with stoppering guide portions only on both ends, with one notch therebetween, and the other locking protrusions are There are two stoppers at both ends and in the center, and two notches are provided, but these combinations are arbitrary, all may have one notch, or they may be provided alternately. Of course, it is possible to provide three notches.
In addition to dispersing as described above, the locking projections are provided in a U shape excluding the annular or opening tab portion, and a plurality of stoppering guides and notches are provided at the bottom. Also good.
[0015]
4A is a bottom view of the cap as in FIG. 1A, FIG. 4B is a side sectional view of the YY cross section of FIG. It is the elements on larger scale of the P section of A).
As described above, in the present invention, it is particularly preferable that the window-shaped concave portion 12 is provided on the outer surface of the skirt portion 3 (FIG. 1C). By providing this window-shaped recess 12, a thin portion is provided in the skirt portion to impart flexibility to the cap, thereby improving the opening performance and facilitating the expansion of the cap in the radial direction at the time of plugging. Is possible.
The shape of the window-shaped recess 12 is not particularly limited to that shown in FIG. 1 (C). However, the lower end of the skirt portion is used as the holding portion from the viewpoint of preventing the cap from being damaged by the stopper and at the time of die cutting during molding. From the viewpoint that it is necessary to ensure a certain thickness at the lower end of the skirt portion, it is preferable that a plurality of the skirt portions are provided in the circumferential direction except for the lower end of the skirt portion.
Furthermore, as shown in FIG. 4 (C), the window-shaped recess 12 is preferably provided at a position overlapping the stopper guide portion 7 in the radial direction. Since the portion provided with the stopper guide portion 7 is thick, by providing the concave window portion in this portion, the thick portion of the skirt portion can be thinned.
[0016]
FIG. 5 is an enlarged sectional side view for explaining the opening tab 11 of the cap shown in FIG. The opening tab 11 includes a flange portion 14 and a plurality of ribs 15 for reinforcing the flange portion 14, and a protrusion 16 for hooking a finger is provided on the lower side of the front end of the flange portion 14. Yes.
In the present invention, by opening the thin skirt portion by deforming the thin skirt portion by easily pushing up the finger near the lower protrusion 16 of the flange portion 14 of the opening tab 11 and pushing it upward, the plug can be easily opened. Can do. Since the cap of the present invention is not opened by breaking the cap, it can be re-plugged, for example, when it is left untreated.
[0017]
FIG. 6 is a side sectional view showing the case where the resin cap 1 of the present invention is applied to the milk bottle 20, and FIG. 7 is a side sectional view showing an enlarged portion of the mouth portion 21 of the milk bottle in FIG. 6. FIG.
6 and 7, the cap 1 is fitted into the mouth 21 of the milk bottle by the skirt portion 3 and the inner plug 10, and is in close contact with the bottle mouth 21 on the inner plug outer surface, the skirt inner surface and the top plate inner surface. Maintains hermeticity. As shown in FIG. 7, when the cap 1 is fitted into the bin mouth 21, the region Q1 on the outer side of the inner plug and the region Q2 on the inner side of the skirt portion overlapped with the shape of the bin mouth in FIG. In addition, the inner plug is elastically deformed so as to be spread radially inward and the skirt portion radially outward. Accordingly, in the region Q, when the cap is applied, the cap is pressed against the container mouth by a force opposite to the direction in which the cap is spread. It is held high.
The milk bottle shown in FIGS. 6 and 7 is an example of a container to which the cap of the present invention is applied. According to this example, no step portion is provided on the outer peripheral surface of the mouth of the milk bottle, The application is engaged by locking at the inclined portion of the outer peripheral surface of the mouth portion. However, if a protrusion is provided on the outer peripheral surface of the container mouth portion, the lower surface of the protrusion and the locking protrusion are of course provided. The upper part of this is engaged and sealed.
[0018]
In the specific examples shown in FIGS. 1 to 7, the sealing engagement portion provided on the cap is the inner plug 10, which makes it possible to maintain high sealing performance of the cap, but is not limited thereto. is not. For example, a conventionally known sealing engagement means can be employed, such as providing an annular seal member that contacts the tip of the container mouth on the inner surface of the cap top plate.
[0019]
In the locking projection in the cap of the present invention, the shape of the notch can be variously changed.
8A is an enlarged cross-sectional view showing the shape of the notch portion of the cap shown in FIGS. 1 to 7, and FIGS. 8B to 8E are enlarged views showing examples of other shapes of the notch portion. It is sectional drawing.
(A) is as described above, but (B) is a notch 8 formed by forming a rectangular recess in the radial direction below the top 5 of the lower part 9 of the locking projection. A portion 17 serving as a guide for stoppering is also provided below the notch 8. According to this aspect, the engagement between the cap and the container can be strengthened, and the sealing performance is improved.
[0020]
(C) is a notch 8 formed by forming a recess extending in the lower part 9 of the locking projection from the lower end of the cap to the vicinity of the top 5 in the axial direction. According to this aspect, in the case of (A) Similarly to the above, the mold can be easily removed from the mold, the moldability is excellent, and the portion projecting inward in the radial direction of the cap is not cut out, so that the container has a good sealability. In this aspect as well as in the case of (B), the lower side surface 17 of the not-cut portion 18 serves as a stoppering guide portion, so that an independent stoppering guide portion is not provided and the locking projection is provided. Correspondingly, it can be provided over the entire circumferential direction. However, in order to further improve the plugging performance, the plugging guide portion is independently provided from the top portion 5 to the lower end of the skirt portion as in the case of (A). More preferably, it is provided.
(D) is obtained by dispersing the notches of (C) in the radial direction. According to this aspect, the same effect as (C) can be obtained, and the same independent as (C) can be obtained. It is preferable to further provide the stopper guide part. Furthermore, (E) is a shape in which the notch has a substantially semicircular shape, and the same effect as in (A) can be obtained in this aspect as well.
[0021]
The resin cap of the present invention can be integrally formed by injection molding or compression molding using a synthetic resin such as polyethylene.
In general, in a synthetic resin cap, since a die is used on the inner surface of the cap, it is preferable that the undercut on the inner surface of the cap is small. However, in the present invention, no undercut other than the locking projection is formed. In addition, when performing die cutting, a certain amount of thickness is required at the lower end portion of the skirt portion. However, in the cap of the present invention, since the window-shaped recess is provided except for the lower end of the cap, the die cutting is easy. And excellent in moldability.
[0022]
【The invention's effect】
In the resin cap of the present invention, by providing a stopper guide portion whose diameter increases downward from the top portion and a notch portion for partially thinning the skirt portion at the lower portion of the locking projection, Flexibility can be imparted to the skirt without weakening the engaging force of the protrusions, which makes it possible to open easily and reliably without the need for force to open the plug. The conflicting performance can be easily balanced.
Further, due to the presence of the stoppering guide, the cap is smoothly introduced into the container mouth along the stoppering guide, and the upper part of the locking projection and the outer peripheral surface of the container mouth are locked, and Breakage of the cap in the stopper can be effectively prevented. Furthermore, the locking projections are provided in a distributed manner in the circumferential direction, and a thin portion is formed between the locking projections, so that the air in the cap can be easily removed during the plugging, and the resistance during the plugging can be reduced. Can be reduced, and the plugging property is also excellent.
In addition, since the engagement member such as the locking projection and the inner plug is firmly fitted to the container mouth and has excellent sealing performance, the contents will not leak, It is suitable for use in a glass container which is excellent in storage stability and particularly excellent in storage stability such as a milk bottle.
[Brief description of the drawings]
FIG. 1 shows an example of a resin cap of the present invention, in which (A) is a bottom view, (B) is a side sectional view, and (C) is a side view.
FIG. 2 is a partially enlarged side sectional view of FIG. 1;
FIG. 3 is a partially enlarged side sectional view of FIG. 1;
4 is a view of the resin cap shown in FIG. 1 from another direction, in which (A) is a bottom view, (B) is a side sectional view, and (C) is a partially enlarged view of a P portion in (A). FIG.
5 is a partially enlarged side sectional view of FIG. 1. FIG.
FIG. 6 is a side sectional view showing a state in which the resin cap of the present invention is applied to a container mouth portion.
7 is a partially enlarged side sectional view of FIG. 6;
FIG. 8 is a partially enlarged side sectional view showing another example of the shape of the notch in the resin cap of the present invention.

Claims (4)

A top plate portion having a sealing engagement portion with the container mouth portion on the inner surface side, a radially inwardly engaging projection portion for engaging with the outer peripheral surface of the container mouth portion on the inner surface side, and below the outer surface side In the resin cap comprising a skirt portion having a plug opening tab partially protruding outward, the locking projection is reduced in a downward direction to reach the top and downward from the top. The stopper is formed of a guide part for a stopper with an increasing diameter and a lower part consisting of a top part or a notch part located below the top part . Each of the protrusions has a stoppering guide part at least in an end part in the circumferential direction or in the vicinity thereof, and has a notch part between the stoppering guide parts . Claim 1 Symbol placement of resin cap, wherein the sealing engagement portion is an inner plug. 3. The resin cap according to claim 1, wherein a plurality of window-shaped concave portions are provided on the outer surface side of the skirt portion so as to be dispersed in the circumferential direction except for a lower end edge of the skirt portion. . 4. The resin cap according to claim 3 , wherein the window-shaped recess is provided in a positional relationship overlapping with the stopper guide portion in the radial direction.

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